Steam trap



June 22, 1937.

'H. J. c. WELLS 2,084,470

STEAM TRAP Filed Sept. 11, 1934 INVENTOR.

JWWM

A TTO EY.

59 lows.

Patented June 22, 1937 UNITED STA E STEAM TRAP Herbert James ClementWells, Jackson Heights, N. Y.

Application September 11, 1934, Serial No. 743,570

8 Claims.

1-.0 object is to provide a simple form of construction of comparativelyfew parts adapted to be conveniently assembled. Another object is toattain convenient and economical manufacture. Other objects andadvantages will be understood from the following specification andaccompanying drawing showing a preferred embodiment of the invention.

Fig. l is a vertical section of the improved trap with the expansibleelement partly in elevation; and Fig. 2 is a plan view.

The structure comprises a main body enclosing portion I having a sideinlet opening 2 for connection to a source of steam or vapor, and adownwardly extending outlet 3 adapted to be ,25 connected to a returnpipe. Above the outlet is a seat 4 having an externally threaded lowerportion engaging the body portion of the valve at the outlet opening andforming a tight joint by an intervening gasket 4a. The seat 4 has anopening t-herethrough for discharge of the condensate.

The top of the body portion is closed by a cap 6 in the form of a nuthaving its lower portion externally threaded to engage the interior wallof thebody portion of the trap. The opening closed by the cap issufiiciently large to permit the removal therewith of the controllingvalve. The valve. structure comprises an expansible and contractibleelement 1 of tubular form and of the A0 helical corrugated metal bellowstype forming screw thread convolutions as indicated in Fig. l. The upperend of therbellows is closed by an end piece 8 of sheet metal having adownwardly extending rim 8a threaded on its interior to re- 5 ceive andenvelop the external thread convolutions of the bellows at its upperend. Thus a firm mechanical connection and support of the bellows withthe end piece B is formed by merely screwing the end piece on the end ofthe bel- This screw joint is also soldered around the joint la to insurethat the end piece hermetically seals the upper end of the bellows. Thecenter of the end piece 8 has a small threaded opening closed by a screw81) for permitting the convenient insertion of the volatile liquidwithin the bellows,

after which a drop of solder may be used to cover the screw for makingan air tight joint or a proper gasket under the screw head may be usedfor that purpose.

The lower inner portion of the cap 6 is machined to form a circularrecess for reception of the end piece 8 which fits within it against ashoulder of the recess. This recess is threaded for reception of thethreaded end of a metal tube 9 which encloses and shields the corrugatedelement F. The end of the tube 9 is nicely fitted over the outside ofthe rim 8a and impinges against a small shoulder formed on the outsideof the rim 8a. Thus when the tube 9 is screwed into the recess of thecap, it holds the end piece 8 firmly in place against its seat in thecap. The tube 9 has an inwardly extending rim 9a at its lower end. Theend piece 8 is die pressed to the general form shown including theformation of the threads on the interior of its rim for engagement withthe bellows 1. Thus the end piece is simply and economically made.

The lower end of the expansible element 1 is closed by another end pieceit! also formed from sheet metal. It has an upwardly extending rim mawhich is internally threaded to receive and envelop the screwconvolutions of the element 7, the screw joint being soldered at 1b tohermetically seal the corrugated tube. The outside of the rim Illa hasvertical extending abutments Hib formed thereon at suitably spacedintervals which engage the interiorci the tube 9 and serve as guides forthe lower end of the tubular element 1. The inwardly extending rim 9aserves as astop to limit the outer position of the end piece it! duringtests. The tube 9 also serves to further protect and shield the bellowsfrom erosion and from particles of foreign matter which might lodge inthe folds of the exterior of the bellows The central portion of endpiece H! is depressed to form a protuberance lfic. This is threaded onits exterior tubular portion to receive anjinternally threaded nut H.The nut has a downwardly extending portion and an inwardly extending rimI la and serves to carry the movable head i2 of the valve. This head hasan outwardly extending rim lZa. at its top for loosely carrying itbetween the interior of the nut E l and the part We. The body portion ofthe valve head I? loosely passes through the opening within the rim Ilaand is spherically shaped with a stem proljecting end i261 entering thevalve seat opening. Within the corrugated element 1 is a metal tube 13which rests on the interior of the end plate ltl and serves as a guidefor the interior of the belprotruding portion, and an element embracinglows.- It also prevents contraction of the bellows beyond a certainlimit by then engaging the interior of the end plate 8; The end piece I0is die pressed to its general form from sheet metal, in

cluding the threads Within the rim Illa for reception of theconvolutions of the lower end of the bellows. It is thus simply andeconomically made and serves not only to. sealthe lower end of thebellows but as a guide within the tube 9 and likewise for carrying thenut which supports the It also serves as a seat impinges when the latteris forced to its closed position. r g

V In operation, the incoming steam from the radiator will heat thecontrolling parts causing the volatile liquid within thebellows tovolatilize". and force the valve to its closed position. Duringtheclosing action, the valvehead I2 is self-ad 'justing being freelymovable in its support to seat itself in proper-alignment and thusinsure complete: closure of the valve. When the condensate hasaccumulated sufficiently to cause the cooling of thecontrolling parts,the vapor of the volatile liquid in the bellows will then condense andreduce the internal pressure and allow' thebellows to contract and openthe valve. ,After the condensate has passed out to the return of thesystem, the incomingsteam will again cause the 010' sure of the valve asabove described; r It is'evident that-bythis invention simplicity andeconomy in manufacture are obtained and the parts are simply andconveniently assembled.

All parts are well protected which together with the rugged constructioninsuresdurability and dependability. Likewise the movable valve elementis made self-aligning by a simple form of' structure. H V V Although apreferred embodiment of thisiinvention is disclosed, variousmodifications may be made without departing from the scope thereof;

and various applications of the invention may be I made to bothautomatic and manually operated valves.

I claim: 1 j 1. Avalve comprising an expansible element of the bellowstype with screw thread convolutions, a sheet metal plate having a' rimenvelop ing the outside of one end of said expansible elemen't, saidsheet metal plate having acentral protruding portion, and an elementembracing said protruding portion; the moveable head of the 'valve'being supported between said last named element and'said protrudingportion.

oping the outside of one end of 'said'expansibl'e element and having ascrew thread engagement therewith and having a centralrscrew threadprotruding portion, and an element embracing said protruding portion andhaving a-; screw ,thread engagement therewith, the movable head of thevalve being supportedbetween' said last named element" and saidprotruding portion.

3. A trap comprisinga cap, an fex'pansible elej ment of the bellows typewith screw thread"con-' volutions,'a sheet'metal'plate supported by saidment. and having a screw thread engagement therewith, saidsecondplatehaving a 'centr'al 2. A ;valve comprising an expansible element ofthe'bellows type with screw thread convolutime, a sheet metal platehaving a rim envelsaid protruding portion, the movable head of the valveof the trap being supportedbetween said last named element and saidprotruding portion;

4. A trap comprising a can, an 'expansible ele-' ment of thebellows typewith screw thread con volutions, a sheet metal plate supported by saidcap and having a rim enveloping the outside of one end of saidexpansible'element andhaving' a screw thread engagement. therewith, a.second sheet metal plate having a rim enveloping the outside of theother end of said expansible element and having a screw threadengagement therewith and having a screw thread central protrudingportion, and a nut threaded on saidproof the trap being looselysupported between said i nut and said protruding portion.

5. Atrap comprising a cap having a recess and having a shoulder in saidrecess, an expansible element of the; bellows type, a plate seatedvagainst said shoulder within said recess and GOV-1 ering one end of andsupporting saidexpansibleg;

element, a tubular shieldlzenclosin'g said'expan} 'sible element andsecured to said cap and holding said plate in position against saidshoulder and expansible' element and having at one end a threadedengagement with said; cap and holding said plate in position and meansfor supporting V the Imovable'head of the valve of the trap from theother end of the said expansible element.

7. A trap comprising a, body having a side inlet and a downwardlyextending outlet, a cap covering an opening said body opposite theoutlet, an expansible element ofthe bellows type supported at one end bysaid cap and subature of=themedium received through said inlet, meansfor supportingthe movable head of the valve of the trap from the otherend of said.

. jected to and responsive to change of temperl expansible'element, anda tubular'shield enclos-J ing said expansible elementand support by saidcap at one end and having an inwardly extend} ing portion at the otherend for limiting th'e maximum expansion of the expansible element.

i 8.; A trap comprising a body having-a side in 7 supported at oneend'by' said cap and subjected to-andresponsive' to change oftemperature of the medium/ receiVed'thiough said inlet, means' let and,a downwardly;extending-outlet, afoap covering an openingiin saidbody'opposite the outlet, an expansible element of the bellows typefor'supporti'ng-the movable head of thejvalve of v t the trap from theother; end ofsaid expansible element and a tubular shield enclosing saidexpan sible element and supported by said cap at one end and having aninwardly extending portion at the W other end forlimiting themaxi'mumexpansion offthe expansible' element, said shield.

havingan interior portionf engaging said exi pansible element forguidingits: niovement.

HERBERT JAlViES CLEMENT WELLS.'

, 15 tr nding-portion, the movable head of the valve

